FIG. 1 shows a conventional blowback autoloading pistol. The pistol comprises three main parts: the grip or lower frame 2, the receiver 4 having a bore 6 and a breech 8, and a breech bolt assembly 10 which slides in the breech 8. The trigger guard 12 is integral with the lower frame 2. A hollow space in the lower frame 2 receives the magazine (not shown), the sear 14, the trigger assembly 16 and the hammer assembly 18. The rear of lower frame 2 has a recess for receiving the hammer or main spring housing assembly 20.
The hammer assembly 18 comprises a hammer 22 which is pivotably mounted to the lower frame 2 by means of a pivot pin 24. In addition, the hammer 22 is pivotably coupled to one end of a strut 26 by means of a pivot pin 28. The axes of the pivot pins 24 and 28 are mutually parallel and separated by a predetermined distance. The other end of strut 26 projects into a recess extending from the endface of a plunger 30. The plunger 30 has is slidably arranged in a cylindrical recess of the main spring housing 32. The plunger 30 and main spring housing 32 are parts of the main spring housing assembly 20. The latter assembly further comprises a hammer spring or main spring 34, which is arranged in the cylindrical recess of the main spring housing 32. One end of main spring 34 is coupled to plunger 30 and the other end of main spring 34 is seated against an end face of the cylindrical recess of main spring housing 32.
The hammer 22 is shown in the cocked position in FIG. 1 and is held in that position by the sear 14. When the hammer is in the cocked position, the main spring 32 is in a compressed state. The sear 14 is pivotably mounted to the lower frame 2 by means of a pivot pin 38. The distal end of the sear 14 engages a notch in the hammer to hold the hammer in the cocked position. The sear 14 is operatively coupled to the trigger 40 by means of a trigger rod (not shown). The trigger 40 is pivotably mounted to the lower frame 2 by means of a pivot pin (not shown) and the trigger rod is pivotably coupled to the trigger by means of a pivot pin and a spring (not shown). The trigger, trigger assembly and associated pivot pins and springs comprise the trigger assembly 16. In response to pulling of the trigger 40, the trigger rod releases the sear 14 and a sear spring (not shown) urges the sear out of engagement with the hammer, freeing the hammer for rotation in response to urging of the main spring. The hammer passes through a slot (not shown) in receiver 4. At the end of the hammer's rotation, the hammer strikes a firing pin 42, shown in FIG. 2.
The firing pin 42 is slidably mounted in a slot in the bolt assembly 10. The slot runs parallel to the axis of the bore 6. The firing pin 42 has a slot 44 which is penetrated by a transverse pin 46 which is inserted crosswise through the body 50 of the bolt assembly 10. The impact of the hammer against the back end of the firing pin drives the firing pin 42 forward. The firing pin spring 48 maintains rearward pressure on the firing pin for safety. The impact of the front tip of the firing pin against a cartridge (not shown) in the bore 6 causes the cartridge to fire. Upon firing the bullet is projected down the bore.
The reaction force of the firing drives the bolt body 50 rearward. During this rearward displacement, the spent casing (not shown) is ejected. As best seen in FIG. 3, the bolt assembly 10 comprises a recoil spring guide 52 comprising a guide rod 54 having a forward portion which slides in a channel formed in the bolt body 50. The rear end of the guide rod 54 is connected to a recoil spring slide 56, which is also part of the recoil spring guide 52. The recoil spring slide 56 has a bearing surface 58 which conforms to the shape of a bolt stop pin 72, against which the recoil spring slide bears.
In accordance with the conventional design of a known autoloading pistol, bolt stop pin 72 is pivotably mounted to an upper portion of the main spring housing 32 by means of a pivot pin 76. The upper end of main spring housing 32 also has a lug 78 which couples with a notch (not shown) in the receiver 4 to hold the receiver and lower frame 2 together. The upper end of the bolt stop pin penetrates a hole 104 in the receiver.
The recoil spring slide also has a pair of guide surfaces 60 which ride on respective tracks 62 on opposing sides of a slot 64 formed in the bolt body 50, as the bolt body recoils in the rearward direction. The width of slot 64 is greater than the diameter of the bolt stop pin 72 to allow the bolt body to slide rearward relative to the bolt stop pin. During rearward displacement of the bolt body, bolt stop pin 72 blocks rearward displacement of the recoil spring slide 56.
The bolt assembly 10 further comprises a recoil spring 66 loosely mounted on the guide rod 54. The recoil spring provides resistance to the bolt body 50 during firing and returns the bolt body to its closed position after firing. One end of recoil spring 66 is connected to the recoil spring slide 56. The other end of recoil spring 66 is connected to the front tenon 68 of the recoil spring guide 52. The front tenon 68 is secured in a transverse recess 70 formed in the bolt body 50. During recoil of the bolt body 50, the front tenon 68 compresses the recoil spring 66 against the recoil spring slide 56. When the force exerted by the compressed recoil spring 66 exceeds the force of bolt recoil, the spring returns the bolt body 50 to its closed position. During the return stroke of the bolt body, the bolt body pushes the next cartridge into the bore. At the end of the return stroke, the bolt body 50 is stopped when contact surface 74 abuts the bolt stop pin 72.
The main spring housing assembly 20 further comprises a disassembly lever 80 which is pivotably mounted to the main spring housing 32 by means of a pivot pin 82. When the disassembly lever 80 is pulled out of the housing, the portion of the lever below the pivot pin 82 pushes the lower end of main spring housing 32 out of the recess in which it is nested in the lower frame 2. The main spring housing 32 can then be pivoted about the pivot pin 76, thereby disengaging the lug 78 from the notch in the receiver. Then the bolt stop pin 72 is pulled axially downward, out of the pistol. With the bolt stop pin 72 removed, the bolt assembly 10 can be slided rearward, out of the breech 8. Then the receiver can be separated from the lower frame. In this disassembled state, the pistol can be cleaned.
The above-described disassembly procedure is relatively complex and time-consuming. It also requires a great deal of manual dexterity on the part of the user. As a result, the process of stripping and cleaning pistols of the above-described type, especially for pistol owners who are not professional gunsmiths, is difficult to master. This has been true for the many years during which such pistols have been manufactured and sold. Thus, there has been a long-felt need among owners of autoloading pistols of this type for a solution to the problem of difficult disassembly.